Receivers (1,11) for receiving radio frequency signals are provided with modulating stages (4,14) between mixing stages (3,13) and filtering stages (5,15) for deltasigma modulating intermediate frequency signals, to shape the quantisation noise out of the frequency band in which the wanted channel is located. Modulating stages (4,14) comprise delta-sigma modulators (41,42,43,90) with low-pass filters (91), quantisers (92) and digitalto-analog converters (93) having a low resolution and therefore a low power consumption. Due to delta-sigma modulating being done through a feedback loop, the receivers (1,11) have become less critical. The low-pass filters (91) comprise time-continuous filters, to avoid antialiasing filtering. The receivers further comprise digital further mixing stages (6, 16) coupled to the filtering stages (5, 15) for generating baseband signals and digital further filtering stages (7, 17) coupled to the further mixing stages (6, 16) for channel selective filtering the baseband signals.

 
Web www.patentalert.com

> Apparatus and method for local broadcasting in the twenty-six megahertz short wave band

~ 00319